Conducting polymer electroluminescence

Polyfarylene vinylene)s form an important class of conducting polymers. Two representative examples of this class of materials will be discussed in some detail here. There are poly(l,4-phenylene vinylcne) (PPV) 1, poly(l,4-thienylene viny-lenc) (PTV) 2 and their derivatives. The polymers are conceptually similar PTV may be considered as a heterocyclic analog of PPV, but has a considerably lowci band gap and exhibits higher conductivities in both its doped and undoped stales. The semiconducting properties of PPV have been shown to be useful in the manufacture of electroluminescent devices, whereas the potential utility of PTV has yet to be fully exploited. This account will provide a review of synthetic approaches to arylene vinylene derivatives and will give details an how the structure of the materials relate to their performance in real devices. 

G. Leising, S. Tasch. W. Graupncr, Fundamentals of Electroluminescence in Paraphcnylene-Typc Conjugaled Polymers and Oligomers, in Handbook of Conducting Polymers (Eds. T. Skotheim, R. Elsenbaumer, J. Reynolds), Marcel Dekker, New York 1997. 

Note 1 Electroluminescent polymers are often made by incorporating luminescent groups or dyes into conducting polymers. 

The cross-coupling polymerization with dihaloarenes leads to poly(phenylene-vinylene)s (PPVs), which are widely employed as conductive and electroluminescent polymers. ... 

A.J. Campbell, M.S. Weaver, D.G. Lidzey, D.D.C. Bradley, Bulk limited conduction in electroluminescent polymer devices, J. Appl. Phys. 84 (1998) 6737-6746. 

It should be noted here for triarylamine networks and dendrimers [104], respectively, the radical cations have interesting properties like the formation of high-spin polyradicals with ferromagnetic coupling [105] or conducting polymers [106]. Very often, triarylamines have been used as the hole-transport layer in electroluminescent devices [107]. 

High-resolution circuitry and active devices employing Langmuir-Blodgett film techniques or polymer-based transistors are being considered for the sophisticated electronics required in future vehicles. Temperature or energy balance in the vehicle could be controlled through conductive polymers or semiconductor deposits on electrochromic windows. Electroluminescent liquid crystals and fluorescent and electrochromic materials used for visual displays show promise for future development. 

Conducting polymers such as polyacetylene, polypyrrole, polyaniline, polythiophene, etc. have been actively studied for use in various fields due to their interesting properties batteries,46 electrochromic displays,47 materials for supercapacitors,48 corrosion protection,49 protecting layers for static electricity,50 materials for organic electroluminescence displays,51 sensing materials,52 etc. Polypyrrole is reported to be extremely rigid, with a semi-crystalline structure. 

Li K., Diaz D. C., He Y., Campbell J. C., and Tsai C., Electroluminescence from porous silicon with conducting polymer film contacts, Appl. Phys. Lett., 64, 2394-2396,... 

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